Getting to know Plants

Sepals → Petals → Stamens → Pistil

Step 1: A flower has four main whorls (circles of parts) arranged from outside to inside. Step 2: The outermost whorl is the sepals — small, leaf-like structures that protect the bud. Step 3: Inside the sepals are the petals — usually colourful, they attract pollinators. Step 4: Further inside are the stamens — the male reproductive parts of the flower. Step 5: The innermost part is the pistil — the female reproductive part, containing the ovary at its base.

Transpiration

Step 1: The polythene bag is sealed around leaves to trap any gases or water vapour that the leaf releases. Step 2: Leaves release water in the form of vapour through tiny pores — this process is called transpiration. Step 3: The water vapour collects inside the sealed bag and cools, forming water droplets. Step 4: This is similar to water vapour condensing into drops on a cold glass. Step 5: Photosynthesis produces food and releases oxygen — it does not directly release water droplets into the bag.

The leaf has prepared starch through photosynthesis

Step 1: In Activity 5, the green colour (chlorophyll) is removed from the leaf using spirit. Step 2: Iodine solution is then applied — iodine turns blue-black only in the presence of starch. Step 3: The blue-black colour confirms starch is present in the leaf. Step 4: This starch was made BY the leaf through photosynthesis using sunlight, water, and carbon dioxide. Step 5: Plants cannot absorb starch from soil or water — they manufacture it themselves, which is why plants are called producers.

Roots absorb water and minerals AND anchor the plant in the soil

Step 1: Plant B dies even though it is watered — this shows that without roots, the plant cannot absorb water and minerals from the soil. Step 2: The roots are the only organs that can absorb water; without them, the plant starves of water. Step 3: Roots also hold the plant firmly in the soil (anchoring) — without roots, the plant can easily fall over. Step 4: Roots do not produce food — that is the job of leaves through photosynthesis. Step 5: Roots do not absorb sunlight or produce chlorophyll — those functions belong to the leaves.